Windshield wiper refill backing strip



FIG. 1 is a perspective view of the top, side and end of a windshield wiper refill backing strip showing my new design which has been broken away in the middle to indicate indeterminate length;

FIG. 2 is a perspective view of the bottom, side and opposite end thereof; and

FIG. 3 is an end elevation view thereof. 

The ornamental design for a windshield wiper refill backing strip, as shown. 